Hi Martin,
It would be interesting to implement a way to get access to the Eyelink files in Brainstorm. It’s a widely used system and having its output in Brainstorm could be useful for various purposes.
However I have very limited resources at the moment to deal with this, so I would need help from you or your collaborators to implement this.
There are a few issues to deal with first, starting from legal considerations. To include anything in Brainstorm, we need it to be compatible with a GPL license.
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This is not an open file format, and the EDF API doesn’t look like open software.
We probably don’t have the right to distribute this (neither as part of the Brainstorm forum, nor as a .zip file posted on this forum).
Could you contact the company and ask them what the actual license is for this library? What are we allowed to do with it, are we allowed to redistribute it, and if not what is the correct distribution path for it? -
The license for the edfImport library is not explicit either, so we need to ask the author the same questions: license and redistribution rights.
It looks like the code comes from a German university, so there is a higher chance to have this solved easily.
We can note that the author didn’t include the “edfapi.dll” in the package so maybe he doesn’t have the right to. -
Once the integration and distribution questions are solved, we have to deal with the technical ones.
Using the call "edfImport(‘file.edf’, [1 1 1]) returns tons of data. How would you like this to be available in Brainstorm?
- Would you like all the values to be accessible as continuous signals?
- If this is the case, there might be sampling issues: is the time sampled regularly? Brainstorm cannot handle irregular time sampling or recordings with gaps.
- What is the difference between “Events” and “Samples” (sorry, I’ve never been using an eye tracking device myself, I’ll a lot of guidance)?
- What is the meaning of all these fields?
- In the, what is the final goal of having this data available in Brainstorm? Can you provide examples?
- The last problem will be the synchronization with MEG/EEG data. If you want the eye tracker data displayed simultaneously with other signals coming from other acquisition devices, we need to solve two issues:
- the sampling rate (Brainstorm can display signals simultaneously only if they have exactly the same time definition)
- the synchronization itself (how do you match the start points after resampling)
=> This will require the development of a separate process, which might be a bit difficult to write properly (but doable with some resource).
I think all this is doable, and will happen a lot faster if you are willing to contribute to the development.
Cheers,
Francois